Elevated Levels of Ultrashort- and Short-Chain Perfluoroalkyl Acids in US Homes and People

• Type of Material: Article
• Authors: Guomao Zheng, Southern University of Science and Technology; Stephanie M. Eick, Emory University; Amina Salamova, Emory University
• Language: English
• Date: 2023-10-11
• Publisher: American Chemical Society
• Publication Version: Final Published Version
• Copyright Statement: © 2023 The Authors. Published by American Chemical Society
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): https://doi.org/10.1021/acs.est.2c06715
• Title of Journal or Parent Work: Environmental Science and Technology
• Volume: 57
• Issue: 42
• Start Page: 15782
• End Page: 15793
• Grant/Funding Information: The authors thank Indiana University and the Indiana Clinical and Translational Sciences Institute for funding of this project.
• Keywords: ultrashort-chain PFAS; PFAS; perfluoropropanoic acid (PFPrA); indoor exposure; PFAA precursors; PFAAs; trifluoroacetic acid (TFA); short-chain PFAS; biomonitoring
• Research Categories: Chemistry, Organic

Abstract

Per- and polyfluoroalkyl substances (PFAS) make up a large group of fluorinated organic compounds extensively used in consumer products and industrial applications. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), the two perfluoroalkyl acids (PFAAs) with 8 carbons in their structure, have been phased out on a global scale because of their high environmental persistence and toxicity. As a result, shorter-chain PFAAs with less than 8 carbons in their structure are being used as their replacements and are now widely detected in the environment, raising concerns about their effects on human health. In this study, 47 PFAAs and their precursors were measured in paired samples of dust and drinking water collected from residential homes in Indiana, United States, and in blood and urine samples collected from the residents of these homes. Ultrashort- (with 2 or 3 carbons [C2–C3]) and short-chain (with 4–7 carbons [C4–C7]) PFAAs were the most abundant in all four matrices and constituted on average 69–100% of the total PFAA concentrations. Specifically, trifluoroacetic acid (TFA, C2) and perfluoropropanoic acid (PFPrA, C3) were the predominant PFAAs in most of the samples. Significant positive correlations (n = 81; r = 0.23–0.42; p < 0.05) were found between TFA, perfluorobutanoic acid (PFBA, C4), and perfluoroheptanoic acid (PFHpA, C7) concentrations in dust or water and those in serum, suggesting dust ingestion and/or drinking water consumption as important exposure pathways for these compounds. This study demonstrates that ultrashort- and short-chain PFAAs are now abundant in the indoor environment and in humans and warrants further research on potential adverse health effects of these exposures.